Driving mechanism for the date indicator in a calendar watch



March 26, 1963 H. STAMM ETAL 3,082,594

DRIVING MECHANISM FOR THE DATE INDICATOR IN A CALENDAR WATCH Filed May 8, 1961 2 Sheets-Sheet 1 March 26, 1963 H. STAMM ETAL 3,082,594

DRIVING MECHANISM FOR THE DATE INDICATOR IN A CALENDAR WATCH Filed May 8, 1961 2 Sheets-Sheet 2 EV/[III kW-H l s; x

United States Patent O land Filed May 8, 1961, Ser. No. 108,499 Claims priority, application Switzerland May 6, 1960 '4 Claims. (Cl. 5858) This invention relates to driving mechanisms for the date indicator in calendar watches and in particular to driving mechanisms comprising a driving member controlled by a rotating finger.

Most of the driving mechanisms of that type, which are known in the art, have the drawback that the date indicator does not jump from one indicating position into the next one, but moves progressively forward during a couple of hours. Since the indications carried by said indicator generally appear one at the time in a window of the watch dial, the date can no longer be read during the time required for the date indicator to pass from one indicating position to the next one.

Driving mechanisms ensuring a sudden jump of the date indicator have already been proposed in the art.

These known mechanisms generally comprise, however, intricate and therefore delicate elements. Several attempts have been made in order to simplify the construction, but the driving mechanisms produced thereby have nevertheless the drawback that they comprise at least a piece extending over a substantial portion of the dial side of the Watch movement thereby causing a substantial increase of the total height thereof.

It is therefore an object of this invention to provide a driving mechanism of the type in which the date indicator jumps from one indicating position to the next one.

Another object of the invention is to provide a driving mechanism of the type mentioned above in which the different members of said mechanism are located only in the vicinity of the date indicator thus leaving the central portion of the watch movement entirely free for the usual motion work and other components of this watch movement.

A more specific object of the invention is to provide said driving mechanism with a driving member constituted by a free plate capable both of rocking about and of shifting along a guiding pin under the action of spring means, said plate comprising a camming surface cooperating with a rotating finger of said driving mechanism.

Still further objects of the invention will become apparent in the course of the following description.

One embodiment of the driving mechanism according to this invention is represented diagrammatically and by way of example in the drawings annexed hereto.

In the drawings:

:FIG. 1 is a plan view of said embodiment showing two difierent working positions, a cover member of said mechanism being removed;

FIG. 2 is a plan view similar to that of FIG. 1 showing a third working position, and

FIG. 3 is a cross-sectional view along line A, B, C, D, E of FIG. 1 on a somewhat larger scale.

The driving mechanism represented in the drawings comprises a date indicator constituted by a ring 1 provided with an inner toothing 2. Ring 1 is mounted for rotary motion on the base plate 3 (FIG. 3) of the framework of a calendar watch. A pin 4 projecting from the dial side of base plate 3 serves as a pivot for an intermediate gear 5 which is driven by the motion work of the watch. Gear 5 meshes with a driving wheel 6 riveted on to a sleeve 7a made integral with a finger 7. Sleeve 3,082,594 Patented Mar. 26, 1963 7a is freely pivoted on a pin 8 of base plate 3. A plate 9 serving as a cover for the driving mechanism of ring 1 is rigidly fixed on to the upper portion of sleeve 7a, thus limiting the axial play of a driving plate 10. The latter extends between cover member 9 and wheel 6 and it is located on the same level as finger 7. This plate is provided with a slot 10:: engaging a guiding pin '11 fixed to base plate 3. Pin 11 is provided at its upper portion with a head 11a to retain plate 10 axially in place. The latter is further provided with a first tooth 12 extending on the side of guiding pin 11 which is opposed to finger 7.

Tooth 12 is arranged for engaging the too-thing 2. Plate 10 is further provided with a second tooth 13 also arranged for cooperation with toothing 2 and extending between finger 7 and said toothing. Plate 10 is still further provided with a projection 10b carrying a camming surface opposite finger 7 and ending with a resilient arm 10d which is arcuate and directed towards tooth 13. The distance from the free end of arm 10d to tooth 13 is somewhat smaller than the diameter of sleeve 7a. Plate 10 finally comprises a projection 14 bent downward and extending below ring 1. A spring 15, located in a recess 3a of base plate 3, acts on the free end of projection v14 so as to urge plate 10 towards guiding pin 11. Under the action of spring 15 plate 10 tends to rest in such a position that theend face of slot 10a bears against pin 11 and that plate It tends to pivot clockwise around said pin, as shown in FIG. 1.

The projection 10b of plate 10, which is provided with the camming surface 100, extends on the side of finger 7 which is opposed to toothing 2 with respect to the plane passing through the axes of pin 11 and finger 7. The finger 7 is thus located in a space comprised between tooth 13 and camming surface lilc. As shown in FIG. 1, the camming surface extends across the path of finger 7. It moreover comprises an indentation 1-6 at its end directed towards arm 10d, so that finger 7 cooperates with said indentation when it rotates clockwise and leaves camming surface 100.

The driving mechanism according to the invention further comprises a detent 1'7 the free end of which engages toothing 2 under the action of a spring 18. Detent 17 is provided with a triangular end portion 19 which is fully engaged between two teeth of toothing 2 by spring 18.

During the greater portion of the day the driving mechanism described rests in the position represented in full lines in FIG. 1. Tooth 12, is removed from toothing 2 while tooth 13 is disposed in the gap formed between the two teeth 2a and 2b. Plate 10 remains in this rest position as long as finger 7 does not come into contact with the camming surface 10c. It will be observed that finger 7, which is driven by the watch movement through the intermediate gear 5 and wheel 6, makes one complete revolutionin twenty-four hours. In said rest position spring 15 presses the end face of slot 10a against the driving pin 11 and the camming surface 100 against the sleeve 7a of finger 7. When the end portion of finger 7 comes in contact with the camming surface "100, it causes plate 10 to rock counterclockwise around pin 11 while bending spring 15. Tooth 12 enters a gap between two teeth of toothing 2 while tooth 13- is removed from said toothing. Plate Ill-thus progressively comes into the position represented in do-and-dash lines in FIG. 1. The spring-pressed detent '1719 and tooth 12 prevent ring 1 from rotating accidentally. Thus, tooth 12 acts as a safety as regards the correct motion of ring 1.

When finger 7 moves on clockwise, its end engages the identation 16 and causes plate 10 to shift towards the right in FIG. 1 While bending spring 15 move. The sizes of the different pieces of the driving mechanism, ac-

' FIG. 1.

cording to the invention, are chosen in such a manner that said shifting motion of plate proceeds until tooth 13 has reached a position opposite the gap between teeth 2b and 2c of toothing 2. In that position of plate 10 finger 7 still engages indentation 16. When continuing its rotation finger 7 thus causes plate 10 to rotate clockwise around pin 11 while still remaining in engaged condition with respect to indentation 16. During the last rocking motion of plate 10, tooth 13 of the latter enters'the gap comprised between teeth 2b and 20 while tooth 12 is removed from toothing 2. At that moment only fiinger 7 leaves indentation 16. Plate 10 is then fully abandoned to the action of spring which causes it to move in a jumping motion towards the left in During this jumping motion, the'camming surface 10c slides against sleeve 7a. Plate 10 moves until the end face of slot 10a butts against pin 11. During this jumping motion of plate 10, tooth 13, which entered the gap between teeth 2b and 2c, catches tooth 2b and causes ring 1 to rotate suddenly through a predetermined angle which is greater than half the circular pitch of toothing 2. One tooth of ring *1 accordingly moves beyond the free end 19 of detent 17 so that the latter causes ring 1 to rotate further on until detent 17-19 is again fully engaged between two teeth of toothing 2 under the action of spring 18.

It will be observed that the resilient arm 10d of plate 10 substantially simplifies assembling the driving mechanism according to the invention. Since sleeve 7a of finger 7 can only be passed through the gap formed between tooth 13 and the end of the resilient arm 10 d by urging the latter away from said tooth, the plate 10 can be set around sleeve 7a before mounting the latter into the watch movement, thus forming a single assembling unit therewith. Arm 10d thus delimits a space in which the sleeve 7a of finger 7 is disposed.

With the improved driving mechanism described above, the date indicator constituted by ring 1 always jumps from one indicating position to the next one so that the date can be correctly read at any time, thus preventing two figures carred by ring 1 from appearing simultaneously in the dial window of the watch. Moreover, the driving mechanism, according to the invention, is wholly located in the vicinity of the toothing 2 of ring 1 so that the different pieces of this mechanism cannot interfere with the other watch elements, for instance, those of the motion work.

While one embodiment of the invention has been described in detail with reference to the accompanying drawings, it should be understood that various changes in the shape, sizes and arrangement of parts will appear 0bvious to those skilled in the art within the scope of the appended claims without departing from the spirit of the invention or sacrificing the advantages thereof.

We claim: 7

1. In. a calendar watch having a ring-shaped date indicator provided with an inner toothing, means for pro ducing a step-by-step drive of said indicator and comprising a guiding pin, a driving member mounted both for sliding motion along said pin and for rocking motion about said pin, spring means acting on said driving member to maintain it normally in a predetermined resting position and, upon a displacement of the driving member away from its predetermined resting position, to bring it back into this resting position first by rocking the same around said guiding pin and then by sliding it therealong, a driving tooth on said driving member engaging the inner toothing of the date indicator when said driving member is in said predetermined position around said guiding pin, said driving tooth leaving said toothing upon a rocking motion of said driving member against the ac tion of said spring means and said driving tooth moving in a tangential direction with respect to said toothing when said driving member slides along the guiding pin, a control finger mounted for rotary motion and normally driven continuously in the same direction, a camming surface on said driving member extending in the path of said control finger and causing said driving member to rock around said guiding pin against the action of said spring means when said camming surface is engaged by said control finger, and an indentation provided on said driving member and located in the path of said control finger, said control finger causing said driving member to slide along said guiding pin when this control finger engages said indentation.

2. In a calendar which according to claim 1, said control finger comprising a hub portion and said driving member abuttingly engaging said hub portion when it has been moved in said predetermined position under the action of said spring means.

3. In a calendar watch according to claim 1, said driving member further comprising a resilient arm extending from said camming surface toward said driving tooth and having a free end spaced at a distance from said driving tooth thereby defining a smaller diameter than the diameter of a hub portion of said control finger, said driving tooth, said camming surface and said resilient arm thereby enclosing a space in which said hub portion of the control finger is disposed.

4. In a calendar watch having a ring-shaped date indicator provided with an inner toothing, means for producing a step-by-step drive of said indicator and comprising a guiding pin, a driving member mounted both for sliding motion along said pin and for rocking motion about said pin between a first and a second predetermined position, spring means acting on said driving member to maintain it normally in a predetermined resting position and, upon a displacement of the driving member away from its predetermined resting position, to bring it back into this resting position first by rocking the same around said guiding pin and then by sliding it therealong, a driving tooth on said driving member engaging the inner toothing of the date indicator when said driving member is in said first predetermined position around said guiding pin, said driving tooth leaving said toothing upon a rocking motion of said driving member against the action of said spring means and said driving tooth moving in a tangential direction with respect to said toot-hing when said driving member slides along the guiding pin, a safety tooth on said driving member being removed from the toothing of the date indicator when said driving member is in said first position around said guiding pin and said safety tooth engaging the toothing of the date indicator when said driving member is rocked into said second position, a control finger mounted for rotary motion and normally driven continuously in the same direction, a camming surface on said driving member extending in the path of said control finger and causing said driving member to rock around said guiding pin against the action of said spring means from said first to said second position when said camming surface is engaged by said control finger, and an indentation pro vided on said driving member and located in the path of said control finger, said control finger causing said driving member to slide along said guiding pin when this control finger engages said indentation.

References Cited in the file of this patent UNITED STATES PATENTS 2,682,775 Thomas July 6, 1954 2,917,933 Harris Dec. 22, 1959 FOREIGN PATENTS 338,766 Switzerland July 15, 1959 

1. IN A CALENDAR WATCH HAVING A RING-SHAPED DATE INDICATOR PROVIDED WITH AN INNER TOOTHING, MEANS FOR PRODUCING A STEP-BY-STEP DRIVE OF SAID INDICATOR AND COMPRISING A GUIDING PIN, A DRIVING MEMBER MOUNTED BOTH FOR SLIDING MOTION ALONG SAID PIN AND FOR ROCKING MOTION ABOUT SAID PIN, SPRING MEANS ACTING ON SAID DRIVING MEMBER TO MAINTAIN IT NORMALLY IN A PREDETERMINED RESTING POSITION AND, UPON A DISPLACEMENT OF THE DRIVING MEMBER AWAY FROM ITS PREDETERMINED RESTING POSITION, TO BRING IT BACK INTO THIS RESTING POSITION FIRST BY ROCKING THE SAME AROUND SAID GUIDING PIN AND THEN BY SLIDING IT THEREALONG, A DRIVING TOOTH ON SAID DRIVING MEMBER ENGAGING THE INNER TOOTHING OF THE DATE INDICATOR WHEN SAID DRIVING MEMBER IS IN SAID PREDETERMINED POSITION AROUND SAID GUIDING PIN, SAID DRIVING TOOTH LEAVING SAID TOOTHING UPON A ROCKING MOTION OF SAID DRIVING MEMBER AGAINST THE ACTION OF SAID SPRING MEANS AND SAID DRIVING TOOTH MOVING IN A TANGENTIAL DIRECTION WITH RESPECT TO SAID TOOTHING WHEN SAID DRIVING MEMBER SLIDES ALONG THE GUIDING PIN, A CONTROL FINGER MOUNTED FOR ROTARY MOTION AND NORMALLY DRIVEN CONTINUOUSLY IN THE SAME DIRECTION, A CAM- 